<template>
  <view>
    <view class="scroll-view-container">
      <!-- 左侧滑动 -->
      <scroll-view scroll-y="true" :style="{height: wh+ 'px'}" class="left-scroll-view">
        <block v-for="(item,i) in cateList" :key="i">
          <view :class="['left-scroll-view-item', i===active?'active':''] " @click=activeChange(i)>{{item.cat_name}}</view>
        </block>
        
      </scroll-view>
      
      <!-- 右侧滑动 -->
      <scroll-view scroll-y="true" :style="{height: wh+ 'px'}" class="right-scroll-view" :scroll-top="scrollTop">
        <view class="cate-lv2" v-for="(item2,i2) in cateLevel2" :key="i2">
          <view class="cate-lv2-title">/ {{item2.cat_name}} /</view>
          <view class="cate-lv3-list">
            <view v-for="(item3, i3) in item2.children" :key="i3" class="cate-lv3-item" @click="gotoGoodsList(item3)">
              <image :src="item3.cat_icon" ></image>
              <text>{{item3.cat_name}}</text>
            </view>
          </view>
          
        </view>
      </scroll-view>
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        wh:0,
        cateList:[],
        active:0,
        //二级分类列表
        cateLevel2:[],
        scrollTop:0
      };
    },
    onLoad(){
      const sysInfo=uni.getSystemInfoSync()
      this.wh=sysInfo.windowHeight
      
      this.getCateList()
    },
    methods:{
      async getCateList(){
        const {data:res}=await uni.$http.get('/api/public/v1/categories')
        if(res.meta.status !== 200) return uni.$showMsg()
        this.cateList=res.message
        this.cateLevel2=res.message[0].children
      },
      activeChange(i){
        this.active=i
        this.cateLevel2= this.cateList[i].children
        this.scrollTop=this.scrollTop===0?1:0
      },
      gotoGoodsList(item){
        uni.navigateTo({
          url:'/subpkg/goods_list/goods_list?cid='+item.cat_id
        })
        
      }
    }
  }
</script>

<style lang="scss">
  .scroll-view-container{
    display: flex;
    .left-scroll-view{
      width: 120px;
      .left-scroll-view-item{
        background-color: #f7f7f7;
        line-height: 60px;
        text-align: center;
        font-size: 12px;
        
        &.active{
          background-color: #FFFFFF;
          position: relative;
          
          &::before{
            content: '';
            display: block;
            width: 3px;
            height: 30px;
            background-color: #c00000;
            position: absolute;
            left: 0;
            top: 50%;
            transform:translateY(-50%);
          }
          
        }
      }
    }
  .cate-lv2-title{
    font-size: 12px;
    font-weight: bold;
    text-align: center;
    padding: 15px 0;
  }
  .cate-lv3-list{
      display: flex;
      flex-wrap: wrap;
      
      
      .cate-lv3-item{
        width: 33.33%;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        margin-bottom: 10px;
        image{
          width: 60px;
          height: 60px;
        }
        text{
          font-size: 12px;
        }
      }
  }
  
  }

</style>
